Missile launch simulator



June 4, 1968 Filed Aug. 23, 1965 Ml] l M. H. BALLER MI SSILE LAUNCH S IMULATOR 2 Sheets-Sheet :zt

DETONATOR United States Patent 3,386,188 MISSILE LAUNCH SIMULATQR Maurice H. Raller, Chevy Chase, Md., assignor to the United States of America as represented by the Secretary of the Navy Filed Aug. 23, 1965, Ser. No. 481,)90 5 Claims. (Cl. 35-25) ABSTRACT OF THE DISCLOSURE A method for simulating a missile launch in an underwater tube type missile system wherein the simulated launch provides a method of conducting launch and post launch operation sequences by filling the missile launch tube with water of a weight equal to that of an operational missile and then allowing an additional amount of water into the tube to simulate post launch conditions.

The invention described herein may be manufactured and used by or for the Government of the United States of America for governmental purposes without the payment of any royalties thereon or therefor.

The present invention relates to a missile launch simulator and a method of operating the same. More particularly, the invention relates to a missile launch simulator for an underwater tube launching system and a method of simulating a launch.

Launching of any missile, and in particular launching of a missile from an underwater platform is an extremely sophisticated and precise operation. Obviously, systems operation must be closely controlled prior to and during launch. In an underwater launch particularly, post launch sequencing and operation must be substantially perfect. The underwater craft must have proper post-launch ballast and the like. Exemplary of a post-launch operation peculiar to an underwater tube type missile system is the flood control procedure disclosed in Patent No. 3,100,421 to T. K. Moy, issued on Aug. 13, 1963. The post-launch procedure is extremely important when a series of missiles are fired from the underwater platform or vessel in rapid succession. It is readily evident that the vessel must recover from the disorientation and oscillations caused by launch of the missile in a short time after launch in order that the next missile in the series may be launched. In one underwater launch system the oscillation does not have to be completely damped out before the next missile is fired. In such a system, with each successive firing, the oscillatory motion increases and the safe firing interval increases. Hence, only a definite number of missiles may be fired safely. The oscillatory motion that occurs after a series of launchings has been termed rip- 1e. p It is extremely expensive to fire a missile or a dummy missile each time that the launch system needs to be tested or each time the launch vehicles crew training or readiness is to be checked. Hence, methods have been developed to simulate a missile launch. One such method utilizes a sabot which provides a method for firing a slug of water of equivalent weight to that of a missile. This method allows for the testing described above. A sabot simulator of this type is described in pending application Ser. No. 440,035, filed Mar. 15, 1965, now Patent No. 3,276,150, entitled Disposable Sabot, to Hamilton et al.

In order that a missile launch not damage the launch tube or the vehicle itself, a motive force other than the missiles engine is utilized to provide initial motive force to the weapon. Once the missile has cleared the vessel, the engines may be ignited without danger to the craft. This type of launch procedure further provides for launch "ice capability from a wide range of ocean depths and surface conditions.

The generator which provides the initial force to a missle also must be utilized to fire the sabot-water slug simulator mentioned hercinbefore. The generator firing itself is an expensive operation and should be minimized.

The instant invention provides a simulated launch which assures proper systems test of much of the launch procedure, equipment operation and proper crew functioning. The method of the instant invention basically comprises filling an empty launch tube, or tubes, with a column of water equivalent in weight to that of a missile; programming the launch control equipment to fire the simulated launch; and upon receipt of the firing signal, allowing an additional weight of water to fill the tube as would occur in a tactical launch. This provides for operation of most of the launch system functions and assures proper equipment function and crew operational readiness. The tactical equipment is maintained intact but for minor modification. Hence, the danger of injury to the tactical system is practically non-existent and changeover time to a tactical system is minimal. The ripple effect mentioned hereinbefore may be simulated by firing a number of such simulated shots. Further, the system of this invention allows for a variety of combinations of shots, i.e., tactical missiles, dummy missiles, sabot-water slug and simulated firings.

An object of the present invention is the provision of a missile launch simulator and the method of operation of the same which requires only slight and temporary modification of the tactical launch system.

Another object is the provision of a launch simulator which is capable of compatibility with a tactical launch and sabot launch equipment.

Yet another object of the present invention is the provision of a launch simulator and method of operation of the same which simulator is extremely inexpensive.

A further object of the present invention is the provision of a launch simulator for an underwater tube type missile system and a method of operation of the same which precludes use of the launch system ejection generator.

Other objects, advantages and novel features of the invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings wherein:

FIG. 1 is a partially cutaway view of the tube of an underwater tube type launch system;

FIG. 2 depicts a partially schematic section of the tube of FIG. 1 and associated control equipment moditied for practice of the invention; and

FIG. 3 is an enlargement of that portion of FIG. 2 enclosed by the circle on FIG. 2.

The tube from which an operational missile is launched performs the following functions: (1) provides a suitable environment for missile stowage and checkout; (2) protects the missile from excessive shock; (3) provides a stable platform for launching the missile; and (4) guides the missile during ejection.

As shown in FIG. 1, the missile launch tube consists of the basic tube 21 supported within an outer jacket 22 by foam sections 23, missile su port ring assembly 24, an um bilical retract mechanism 25, in'tertube seals 26, bellows 27, a diaphragm installation 39', pressurization and drain hoses 29, a hatch pressurization seal 31, access doors 33, electrical installations 34 both on the tube and this support ring, and a vertical support adapter 35. Associated with each launch tube are shock absorbers, generally indicated at 36, consisting primarily of vertical liquid springs 37, and upper and lower lockout cylinders 38.

The liquid springs 37 in conjunction with the support materials between the basic tube and jacket support the launch tube and reduce external shocks. The lockout cylindens 38 hold the tube 21 rigid during missile loading, unloading and launching.

The missile (not shown) is supported vertically within its launch tube 21 by the laterally flexible support ring 24. This is at the base of the basic tube 21 and is held down by the missile holddown clamp (to be discussed hereinafter).

Access to the missile is provided by the access door mechanism 33. The sections 23 between the basic tube and the jacket, and the liquid springs 37 protect the missile from external shock. Temperature and humidity control within the tube is provided by the pressurization hoses 29 and seals 31 in conjunction with equipment on the launch platform (not shown). A diaphragm 39 at the top of the tube 21 protects the missile from sea water when the hatch 30 (shown in FIG. 2) of the launch vehicle is opened and enables the vehicles pressurization system to maintain a prelaunch pressure within the tube 21 slightly higher than that of the sea water above the diaphragm 39. Missile guidance and control commands, monitoring the checkout signals, are transmitted through the umbilical, which is automatically retracted from the missile during launch by the umbilical retract mechanism 25. The same umbilical supplies temperature conditioning water to the missile guidance package.

During the launch count down the missile base is unclamped from the support ring 24. The lockout cylinders 31 are pressurized to form a firm launching platform. At the instant of launch, the diaphragm 39 is ruptured by a signal sent from the switches on the support ring 24, indicative that the missile is in motion. Monitoring and control of the tubes prelaunch condition is accomplished by an electrical control system (not shown). All signals are terminated at a missile control center 41 (see FIG. 2) and all signals to the launch tube complex are originated therefrom.

As stated hereinbefore, simulated launch provides a method of conducting launch and post launch operation sequence for the launcher without expenditure of an external power source; that is, the ejection generator (not shown). The simulated launch procedure activates all the tactical launch equipment, with the exception of one unit; that is, a trigger inverted module 42 of the firing unit, umbilical retracting device 25, and moisture and humidity monitoring circuits. A simulated launch is thus the most economical method of performing launch exercises for pretraining or launch checkout purposes. The launch procedure closely parallels that for tactical missile launching and can be performed either when the vehicle is surfaced or submerged.

For submerged operations, the launch tube is filled with water 51 equivalent to the weight of an operational missile. A signal from the trigger invertor module activates the solenoid which in turn activates the dummy missile simulator. The dummy unit depresses the plunger on the missile first-motion switch which transmits a detonation signal to rupture the diaphragm 39. Since the hatch cover is opened, water flows into the tube filling the remainder of the tube. This simulates the weight and quantity of water in a tube after a launch and allows for operational checks of the post-launch system.

One of the advantages of the simulated launch is that the launch tube 21 and the missile control center 41 need be modified only slightly, thus providing a minimum chance for damage to the tactical missile launcher.

Dynamic missile simulators 43, FIG. 3, which are used in the sabot simulated launch are installed on the support ring 24. The function, structure and operation of the dynamic missile simulators are described in Patent No. 3,128,671, issued on Apr. 14, 1964 to W. H. Mairs et al. Basically the blast responsive device 52, in a sabot launcher is activated by firing of the gas generator which depresses the plunger 46 of the missile first-motion switch 43, causing rupture of the diaphragm 39. Since no gas generator is expended in the practice of the instant invention, a solenoid 53 is placed in juxtaposition to the member 52.

Before launch, each dynamic simulator 43 holds down its associated departure switch plunger 46 to provide a signal to the missile control system indicating that the missile is in place. Upon generation of a trigger signal from the missile control center 41, energization of the dynamic missile simulator solenoids 53 releases the departure switch plungers 46 to simulate the missiles first motion. The dummy triggering inverter unit 42 at the missile control center transmits the release signal from the launching relay to the missile simulator solenoids 53 via cable 45, cable connectors 47, cable 48, umbilical pass through connector 49 and cables 50 upon launch command. This unit 42 is inserted into the socket in the missile command center which would normally receive a tactical trigger inverter unit thus providing a module that is tailored specifically to simulator launch requirements. The dummy unit may be of the form of an arcsuppression rectifier and associated wiring enclosed in a case similar in size and appearance to a tactical inverter unit with the exception of an added receptacle on the front cover. The added receptacle on unit 42 and the umbilical pass through connector 49 permits use of exist ing launcher components without modification to the permanent control wiring of the missile. Since the tube is partially filled with water for the simulated firing, the dummy moisture probe 44 prevents occurrence of the usual alarm indicative of moisture in the tube discussed hereinbefore and hence, prohibits imposition of a hold on the launch due to the water in the tube. During prelaunch preparations, the cable that would carry a hold signal to the missile control center due to excess moisture in the tube is disconnected and the dummy probe is installed. The dummy probe which presents a signal to the missile control system indicative of dry tube, consists of an inductor device which presents an impedance equal to that normally presented when the tube is in fact in a dry condition. A snorkel unit 54 is installed on the inner wall 21 of the launch tube to permit pressurization of the under diaphragm space above the water column. Essentially, this consists of the vertically mounted tube fitted with the lower end flange. This flange mates with the pressurization port to which it is attached before filling the tube with water. The snorkel thus prevents water from entering the pressurization system piping and valves on the launch tube exterior.

Box 55 serves as an electrical signal delay which is located on the outer tube Wall 22 and provided so that the signal to the detonators on the diaphragm may be delayed in time. Hence, a series of tubes may be fired thereby providing the ripple efiect discussed hereinabove. Box 55, as illustrated in FIG. 2, is series connected to a junction box 51 which in turn is electrically connected to units 43.

Thus, a method of simulating the firing of a missile from an underwater tube type launch system requiring a minimum expenditure and minimum changeover from the tactical launch system has been fully disclosed.

Obviously many modifications and variations of the present invention are possible in the light of the above teachings. It is therefore to be understood that within the scope of the appended claims the invention may be practiced otherwise than as specifically described.

What is claimed is:

1. A method of simulating a missile launch from a floating vessel having an underwater vertical tubular missile launch device comprising the steps of partially filling said vertical tube with water to a first level equivalent in weight to the weight of a missile that is normally launched from said tube; providing a temporary barrier for said tube to prevent additional water from entering; and instantaneously removing said barrier to allow an inrush of an additional amount of water to enter said 5 6 tube, said additional amount being equal to that system, whereby the presence of water in said tube will water necessary to rock the vessel in a manner siminot cause a hold signal to be placed on the launch prolar to that occasioned by an actual missile launchcedure. ing and thereby simulating post launch conditions. 5. The method of claim 3 further comprising connect- 2. The method of claim 1 wherein said temporary 5 ing a pressurization port above said first water level in barrier comprises a rupterable diaphragm located at the said tube, thereby maintaining a normal pressure on the open end of said tube. tube side of said rupturable diaphragm.

3. The method of claim 2 wherein the step of removing the barrier further comprises References Cited activating a signal from a missile control center on said 10 UNITED STATES PATENTS vessel to provide a simulated firing signal to a plurality of solenoids located within said tube, said soleii qi i noids being located in a juxtaposition to dynamic 3128671 4/1964 i er 6 1 7 missile simulators within said tube and wherein said 3276150 10/1966 3 solenoids activate said dynamic simulators to pro- 15 421 8/1963 1 3 ton et 89 7 vide a simulated imissile-first-motion signal to said rulpturable diaphragm thereby rupturing the dia- EUGENE R CAPOZIO Primary Examiner p ragm. 4. The method of claim 1 further comprising connect- R- WEIG, A sisifmt Examin r. ing a dummy moisture detector probe to said launch 20 

